While it's too soon to declare victory, "we are confident that we will win this fight," Putnam adds.

Part of the credit, officials say, should go to "canine detector teams" that are sniffing out snails in places that are tough for humans to search.

According to South Florida's WTVJ-TV, one of the Labrador Retrievers out hunting snails is Bear — a U.S. Department of Agriculture canine who recently has been finding hundreds of snails each week (which is fewer than were being discovered last year, a decline that officials think is a sign they're making progress).

As we said back in September 2011 when the snail invasion was detected, the snails eat about 500 different types of plants and can spread a parasite that causes a form of meningitis. Florida's agriculture commission adds that:

"The snails can also cause structural damage to buildings; they consume plaster and stucco to acquire the calcium needed by the snails to grow their large shells. In large numbers, GALS can cause extensive damage."

It's thought that the invasion began with the smuggling of a few snails into Florida by a man who practices a traditional African religion. He reportedly convinced some followers to drink the snails' juices. They became violently ill.